“To select FIVE images in a career of about 7 years is not easy,” Ugandan photographer Edward Echwalu writes in his email. “It was probably the most challenging editorial decision I have ever come across.” I took it as a gentle reminder we might be asking photographers the impossible in our “favorite photographs” series. That said, and after many tough choices by previous photographers, the results so far have always been revealing. Here are Edward Echwalu’s 5 favorite photographs, and some words on how they came into being: